perf check: Introduce 'check' subcommand

Currently the presence of a feature is checked with a combination of
perf version --build-options and greps, such as:

    perf version --build-options | grep " on .* HAVE_FEATURE"

Instead of this, introduce a subcommand "perf check feature", with which
scripts can test for presence of a feature, such as:

    perf check feature HAVE_FEATURE

'perf check feature' command is expected to have exit status of 0 if
feature is built-in, and 1 if it's not built-in or if feature is not known.

Multiple features can also be passed as a comma-separated list, in which
case the exit status will be 1 only if all of the passed features are
built-in. For example, with below command, it will have exit status of 0
only if both libtraceevent and bpf are enabled, else 1 in all other cases

    perf check feature libtraceevent,bpf

The arguments are case-insensitive.
An array 'supported_features' has also been introduced that can be used by
other commands like 'perf version --build-options', so that new features
can be added in one place, with the array

Committer testing:

  $ perf check feature libtraceevent,bpf
           libtraceevent: [ on  ]  # HAVE_LIBTRACEEVENT
                     bpf: [ on  ]  # HAVE_LIBBPF_SUPPORT
  $ perf check feature libtraceevent
           libtraceevent: [ on  ]  # HAVE_LIBTRACEEVENT
  $ perf check feature bpf
                     bpf: [ on  ]  # HAVE_LIBBPF_SUPPORT
  $ perf check -q feature bpf && echo "BPF support is present"
  BPF support is present
  $ perf check -q feature Bogus && echo "Bogus support is present"
  $

Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240904061836.55873-3-adityag@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 82 insertions, 0 deletions

diff --git a/tools/perf/Documentation/perf-check.txt b/tools/perf/Documentation/perf-check.txt
new file mode 100644
index 000000000000..b081514d240a
--- /dev/null
+++ b/tools/perf/Documentation/perf-check.txt
@@ -0,0 +1,82 @@
+perf-check(1)
+===============
+
+NAME
+----
+perf-check - check if features are present in perf
+
+SYNOPSIS
+--------
+[verse]
+'perf check' [<options>]
+'perf check' {feature <feature_list>} [<options>]
+
+DESCRIPTION
+-----------
+With no subcommands given, 'perf check' command just prints the command
+usage on the standard output.
+
+If the subcommand 'feature' is used, then status of feature is printed
+on the standard output (unless '-q' is also passed), ie. whether it is
+compiled-in/built-in or not.
+Also, 'perf check feature' returns with exit status 0 if the feature
+is built-in, otherwise returns with exit status 1.
+
+SUBCOMMANDS
+-----------
+
+feature::
+
+        Print whether feature(s) is compiled-in or not, and also returns with an
+        exit status of 0, if passed feature(s) are compiled-in, else 1.
+
+        It expects a feature list as an argument. There can be a single feature
+        name/macro, or multiple features can also be passed as a comma-separated
+        list, in which case the exit status will be 0 only if all of the passed
+        features are compiled-in.
+
+        The feature names/macros are case-insensitive.
+
+        Example Usage:
+                perf check feature libtraceevent
+                perf check feature HAVE_LIBTRACEEVENT
+                perf check feature libtraceevent,bpf
+
+        Supported feature names/macro:
+                aio                     /  HAVE_AIO_SUPPORT
+                bpf                     /  HAVE_LIBBPF_SUPPORT
+                bpf_skeletons           /  HAVE_BPF_SKEL
+                debuginfod              /  HAVE_DEBUGINFOD_SUPPORT
+                dwarf                   /  HAVE_DWARF_SUPPORT
+                dwarf_getlocations      /  HAVE_DWARF_GETLOCATIONS_SUPPORT
+                dwarf-unwind-support    /  HAVE_DWARF_UNWIND_SUPPORT
+                get_cpuid               /  HAVE_AUXTRACE_SUPPORT
+                libaudit                /  HAVE_LIBAUDIT_SUPPORT
+                libbfd                  /  HAVE_LIBBFD_SUPPORT
+                libcapstone             /  HAVE_LIBCAPSTONE_SUPPORT
+                libcrypto               /  HAVE_LIBCRYPTO_SUPPORT
+                libdw-dwarf-unwind      /  HAVE_DWARF_SUPPORT
+                libelf                  /  HAVE_LIBELF_SUPPORT
+                libnuma                 /  HAVE_LIBNUMA_SUPPORT
+                libopencsd              /  HAVE_CSTRACE_SUPPORT
+                libperl                 /  HAVE_LIBPERL_SUPPORT
+                libpfm4                 /  HAVE_LIBPFM
+                libpython               /  HAVE_LIBPYTHON_SUPPORT
+                libslang                /  HAVE_SLANG_SUPPORT
+                libtraceevent           /  HAVE_LIBTRACEEVENT
+                libunwind               /  HAVE_LIBUNWIND_SUPPORT
+                lzma                    /  HAVE_LZMA_SUPPORT
+                numa_num_possible_cpus  /  HAVE_LIBNUMA_SUPPORT
+                syscall_table           /  HAVE_SYSCALL_TABLE_SUPPORT
+                zlib                    /  HAVE_ZLIB_SUPPORT
+                zstd                    /  HAVE_ZSTD_SUPPORT
+
+OPTIONS
+-------
+-q::
+--quiet::
+        Do not print any messages or warnings
+
+        This can be used along with subcommands such as 'perf check feature'
+        to hide unnecessary output in test scripts, eg.
+        'perf check feature --quiet libtraceevent'